Phylogenetic and Evolutionary Relationships among Yellow Fever Virus Isolates in Africa

ABSTRACT Previous studies with a limited number of strains have indicated that there are two genotypes of yellow fever (YF) virus in Africa, one in west Africa and the other in east and central Africa. We have examined the prM/M and a portion of the E protein for a panel of 38 wild strains of YF virus from Africa representing different countries and times of isolation. Examination of the strains revealed a more complex genetic relationship than previously reported. Overall, nucleotide substitutions varied from 0 to 25.8% and amino acid substitutions varied from 0 to 9.1%. Phylogenetic analysis using parsimony and neighbor-joining algorithms identified five distinct genotypes: central/east Africa, east Africa, Angola, west Africa I, and west Africa II. Extensive variation within genotypes was observed. Members of west African genotype II and central/east African genotype differed by 2.8% or less, while west Africa genotype I varied up to 6.8% at the nucleotide level. We speculate that the former two genotypes exist in enzootic transmission cycles, while the latter is genetically more heterogeneous due to regular human epidemics. The nucleotide sequence of the Angola genotype diverged from the others by 15.7 to 23.0% but only 0.4 to 5.6% at the amino acid level, suggesting that this genotype most likely diverged from a progenitor YF virus in east/central Africa many years ago, prior to the separation of the other east/central African strains analyzed in this study, and has evolved independently. These data demonstrate that there are multiple genotypes of YF virus in Africa and suggest independent evolution of YF virus in different areas of Africa.

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Genome analysis and phylogenetic relationships between east, central and west African isolates of Yellow fever virus

Journal of General Virology ◽

10.1099/vir.0.81236-0 ◽

2006 ◽

Vol 87 (4) ◽

pp. 895-907 ◽

Cited By ~ 25

Author(s):

Jana J. von Lindern ◽

Sarah Aroner ◽

Nicholas D. Barrett ◽

Jason A. Wicker ◽

C. Todd Davis ◽

...

Keyword(s):

Amino Acid ◽

Yellow Fever ◽

Genome Analysis ◽

Yellow Fever Virus ◽

Prototype Strain ◽

West African ◽

Fever Virus ◽

Full Genome ◽

Genome Database ◽

East Central

Yellow fever virus (YFV), a reemerging disease agent in Africa and South America, is the prototype member of the genus Flavivirus. Based on examination of the prM/M, E and 3′ non-coding regions of the YFV genome, previous studies have identified seven genotypes of YFV, including the Angolan, east/central African and east African genotypes, which are highly divergent from the prototype strain Asibi. In this study, full genome analysis was used to expand upon these genetic relationships as well as on the very limited full genome database for YFV. This study was the first to investigate genomic sequences of YFV strains from east and central Africa (Angola71, Uganda48a and Ethiopia61b). All three viruses had genomes of 10 823 nt in length. Compared with the prototype strain Asibi (from west Africa) they were approximately 25 % divergent in nucleotide sequence and 7 % divergent in amino acid sequence. Comparison of multiple flaviviruses in the N-terminal region of NS4B showed that amino acid sequences were variable and that west African strains of YFV had an amino acid deletion at residue 21. Additionally, N-linked glycosylation sites were conserved between viral genotypes, while codon usage varied between strains.

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Introduction

10.1093/oso/9780198826224.003.0001 ◽

2018 ◽

Author(s):

Marina Sharpe

Keyword(s):

West Africa ◽

Great Lakes ◽

East Africa ◽

North Africa ◽

Southern Africa ◽

Theoretical Approach ◽

Central Africa ◽

Horn Of Africa ◽

Refugee Protection

This introductory chapter begins by presenting the book’s structure in section A. Section B then delineates the book’s contours, outlining four aspects of refugee protection in Africa that are not addressed. Section C provides context, with a contemporary overview of the state of refugee protection in Africa. It also looks at the major aspects of the refugee situations in each of Africa’s principal geographic sub-regions: East Africa (including the Horn of Africa), Central Africa and the Great Lakes, West Africa, Southern Africa, and North Africa. Section D then concludes with an outline of the theoretical approach to regime relationships employed throughout the book.

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Molecular epidemiology of yellow fever virus in Africa: A perspective of the phylogeographic split between East/Central African and West African lineages

Acta Tropica ◽

10.1016/j.actatropica.2021.106199 ◽

2021 ◽

pp. 106199

Author(s):

Yan Li

Keyword(s):

Molecular Epidemiology ◽

Yellow Fever ◽

Yellow Fever Virus ◽

West African ◽

Fever Virus ◽

East Central

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Molecular investigation of the Pfmdr1 gene of Plasmodium falciparum isolates in Henan Province imported from Africa

Parasitology ◽

10.1017/s0031182018001609 ◽

2018 ◽

Vol 146 (3) ◽

pp. 372-379 ◽

Cited By ~ 2

Author(s):

Chengyun Yang ◽

Ruimin Zhou ◽

Ying Liu ◽

Suhua Li ◽

Dan Qian ◽

...

Keyword(s):

South Africa ◽

West Africa ◽

East Africa ◽

North Africa ◽

Migrant Workers ◽

Central Africa ◽

Henan Province ◽

Pfmdr1 Gene ◽

Antimalarial Resistance ◽

African Migrant

AbstractEfficacious antimalarial drugs are important for malaria control and elimination, and continuous monitoring of their efficacy is essential. The prevalence and distribution of Pfmdr1 were evaluated in African migrant workers in Henan Province. Among 632 isolates, 13 haplotypes were identified, NYSND (39.87%, 252/632), YYSND (2.85%, 18/632), NFSND (31.01%, 196/632), NYSNY (0.47%, 3/632), YFSND (13.77%, 87/632), NFSNY (0.32%, 2/632), YYSNY (2.06%, 13/632), YFSNY (0.16%, 1/632), N/Y YSND (1.90%, 12/632), N Y/F SND (6.17%, 39/632), N/Y Y/F SND (0.47%, 3/632), YYSN D/Y (0.16%, 1/632) and N/Y FSND (0.79%, 5/632). The highest frequency of NYSND was observed in individuals from North Africa (63.64%, 7/11), followed by South Africa (61.33%, 111/181), Central Africa (33.33%, 56/168), West Africa (28.94%, 68/235) and East Africa (27.03%, 10/37) (χ2 = 54.605, P < 0.05). The highest frequency of NFSND was observed in East Africa (48.65%, 18/37), followed by West Africa (39.14%, 92/235), Central Africa (26.79%, 45/168), South Africa (22.65%, 41/181) and North Africa (9.09%, 1/11) (χ2 = 22.368 P < 0.05). The mutant prevalence of codons 86 and 184 decreased. These data may provide complementary information on antimalarial resistance that may be utilized in the development of a treatment regimen for Henan Province.

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THE RELATIONSHIP OF YELLOW FEVER OF THE WESTERN HEMISPHERE TO THAT OF AFRICA AND TO LEPTOSPIRAL JAUNDICE

Journal of Experimental Medicine ◽

10.1084/jem.51.3.493 ◽

1930 ◽

Vol 51 (3) ◽

pp. 493-517 ◽

Cited By ~ 5

Author(s):

W. A. Sawyer ◽

S. F. Kitchen ◽

Martin Frobisher ◽

Wray Lloyd

Keyword(s):

Yellow Fever ◽

Yellow Fever Virus ◽

Fever Virus ◽

Western Hemisphere ◽

The Other ◽

Pronounced Difference ◽

Rockefeller Institute ◽

The One ◽

Relationship Of ◽

The Relationship

1. The yellow fever now in South America, the present yellow fever of Africa and the historic yellow fever of Panama and other American countries are the same disease. This conclusion is based on cross immunity tests in monkeys with strains of yellow fever virus from Africa and Brazil and on tests of sera from 25 persons, who had recovered from yellow fever in various places and at various times, for the power to protect monkeys against African or Brazilian virus strains. 2. Cases of leptospiral jaundice (Weil's disease) were present among those diagnosed as yellow fever in the recent epidemic in Rio de Janeiro. This is shown by the isolation of cultures of leptospirae from the blood of two patients by H. R. Muller and E. B. Tilden of The Rockefeller Institute, and by the demonstration by us of protective power against leptospirae and absence of protective power against yellow fever virus in the sera from two persons after recovery. The isolation of leptospirae by Noguchi and other investigators from the blood of occasional patients in past epidemics of yellow fever in a number of American countries indicates that leptospiral jaundice was present then as well and was diagnosed clinically as yellow fever. 3. The absence of protective power against leptospirae shown by the Brazilian sera which protected against yellow fever virus and the absence of protective power against yellow fever virus in the sera that protected against leptospirae point to the probability that American yellow fever is not the combined effect of leptospirae and yellow fever virus. The position of L. icteroides, isolated by Noguchi during yellow fever epidemics, now appears to be not that of a secondary invading microorganism in cases of virus yellow fever, but that of the incitant of a form of infectious jaundice, sometimes fatal, often coincident in its appearance with typical yellow fever and apparently indistinguishable from it clinically. This leptospiral disease has not hitherto been separated from true yellow fever. Noguchi's discoveries become; therefore, of the greatest significance in respect to the epidemiology and causation of yellow fever and of infectious jaundice, previously confused one with the other. In all outbreaks of supposed yellow fever hereafter the existence of the two kinds of jaundice, one due to yellow fever virus and the other to leptospirae will have to be taken into account. Only the former probably is spread by mosquitoes and requires anti-mosquito measures for its control. 4. The only difference observed by us between the American and African strains of yellow fever virus was a pronounced difference in virulence for monkeys. The virulence of the two African strains studied was very high while that of the one American strain was highly variable and usually low.

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Peoples of North Africa. Peoples of East Africa. Peoples of West Africa. Peoples of Central Africa. Peoples of Southern Africa. Nations of Africa

The International Journal of African Historical Studies ◽

10.2307/221492 ◽

1998 ◽

Vol 31 (3) ◽

pp. 647

Author(s):

John M. Cinnamon

Keyword(s):

West Africa ◽

East Africa ◽

North Africa ◽

Southern Africa ◽

Central Africa

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Boletes from South and East Central Africa – I

Edinburgh Journal of Botany ◽

10.1017/s0960428600000585 ◽

1992 ◽

Vol 49 (3) ◽

pp. 343-361 ◽

Cited By ~ 6

Author(s):

Roy Watling ◽

Evelyn Turnbull

Keyword(s):

Central Africa ◽

The Other ◽

New Combinations ◽

East Central

Fifteen boletes (Basidiomycotina) distributed in the following genera: Afroboletus (1), Aureoboletus (1), Boletellus (1), Gyroporus (2), Phlebopus (1), Phylloporus (1), Pulveroboletus (5), Suillus (1) Tuboseta (1), and Veloporphyrellus (1) are recorded from Zambia. Four of these collections cannot be assigned to any formerly documented stirps. Two new combinations are proposed and full descriptions of the other collections are given. Afroboletus azureotinctus and Veloporphyrellus africanus are described as new; Tuboseta brunneosetosa var. retipes is recorded from Cameroon & Zimbabwe in addition to Zambia.

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